Fabrication of polystyrene colloidal crystal film by electrophoretic deposition

[Display omitted] •Colloidal crystals of amorphous polystyrene spheres were arranged by the electrophoretic deposition.•Use of mixture solvent of ethanol and water provides closed packing structure.•Over 50 cm2 colloidal crystal films were fabricated by the EPD technique in 5 min. Proper conditions for the formation of a colloidal crystal film by the electrophoretic deposition process were investigated in detail using monodisperse polystyrene (PS) colloidal spheres. Removal of the ionic contaminants and application of a pulsed current were effective in suppressing the electrolysis of water and obtaining a uniform film, but it was not possible to obtain colloidal crystals in which the particles were closely and periodically packed. Mixing EtOH at a high concentration with an aqueous PS suspension and withdrawing the substrate from the suspension at a moderate rate after the EPD process were found to be the key for the successful fabrication of colloidal crystal films. It was demonstrated that the formation of large area colloidal crystal films by the EPD technique was also possible. The advantage of the EPD process for scale up was successfully shown, taking into account the fast film fabrication rate.